Patent US5517464A successfully refreshed from Google Patents.
US5517464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated modulator and turbine-generator for a measurement while drilling tool
Assignee: Schlumberger Technology Corp
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Filing: 1994-05-04
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Granted: 1996-05-14
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Expires: 2014-05-04
Abstract
Abstract An integrated modulator and turbine-generator includes a turbine impeller which is directly coupled by a drive shaft to a modulator rotor downstream from the impeller. The modulator rotor is further coupled by a drive shaft and a gear train to a three phase alternator downstream of the modulator rotor. The modulator stator blades are arranged downstream of and adjacent to the modulator rotor and the alternator is provided with a Hall effect tachometer. The turbine impeller directly drives the modulator rotor and the alternator generates power. The speed of rotation of the modulator rotor is adjusted by reference to the speed of rotation of the alternator as indicated by the tachometer and to a reference frequency. A control circuit including an electromagnetic braking circuit coupled to the tachometer and the stator windings of the alternator stabilizes the alternator speed and thus the rotor speed and modulates the rotor to obtain the desired frequency of the mudborne pressure wave by selectively shorting the stator windings of the alternator. During periods when braking is not applied, the alternator generates power for control and sensor electronics.
Inventors
- 👤 Daniel Lerner
- 👤 Peter Masak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:25
CPC Classifications
E; E21; E21B; E21B41/00; E21B41/0085; E21B47/00; E21B47/12; E21B47/14; E21B47/18; E21B47/20
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
133 words
An apparatus for use in a borehole having borehole fluid flowing therethrough, said apparatus comprising: a) a tool housing having an open end for receiving the borehole fluid; b) a drive shaft mounted for rotation in said housing; c) a turbine impeller mechanically coupled to said drive shaft such that the flowing borehole fluid causes said turbine impeller to rotate; d) a modulator rotor mechanically coupled to said drive shaft such that rotation of said turbine impeller causes said modulator rotor to rotate; e) a modulator stator mounted in said housing adjacent said modulator rotor such that rotation of said modulator rotor relative to said modulator stator creates pressure pulses in the borehole fluid; and f) a controllable braking means for selectively braking rotation of said modulator rotor to modulate said pressure pulses.
Claim 2
Independent Claim
133 words
An apparatus for use in a borehole having borehole fluid flowing therethrough, said apparatus comprising: a) a tool housing having an open end for receiving the borehole fluid; b) a drive shaft mounted for rotation in said housing; c) a turbine impeller mechanically coupled to said drive shaft such that the flowing borehole fluid causes said turbine impeller to rotate; d) a modulator rotor mechanically coupled to said drive shaft such that rotation of said turbine impeller causes said modulator rotor to rotate; e) a modulator stator mounted in said housing adjacent said modulator rotor such that rotation of said modulator rotor relative to said modulator stator creates pressure pulses in the borehole fluid; and f) a controllable braking means for selectively braking rotation of said modulator rotor to modulate said pressure pulses.
Claim 3
Dependent Claim
24 words
An apparatus according to claim 1, further comprising: g) an alternator coupled to said drive shaft, said alternator having at least one stator winding.
Claim 4
Dependent Claim
51 words
An apparatus according to claim 2, wherein: said controllable braking means comprises a control circuit coupled to said at least one stator winding for selectively shorting said at least one stator winding to electromagnetically brake said alternator and thereby selectively brake rotation of said modulator rotor to modulate said pressure pulses.
Claim 5
Dependent Claim
30 words
An apparatus according to claim 3, further comprising: h) gear means coupled between said drive shaft and said alternator for causing said alternator to rotate faster than said drive shaft.
Claim 6
Dependent Claim
16 words
An apparatus according to claim 4, wherein: said gear means has a ratio of substantially 14:1.
Claim 7
Dependent Claim
34 words
An apparatus according to claim 3, further comprising: h) tachometer means coupled to one of said alternator and said drive shaft and coupled to said control circuit for determining rotational speed of said alternator.
Claim 8
Dependent Claim
15 words
An apparatus according to claim 6, wherein: said tachometer means is a Hall effect sensor.
Claim 9
Dependent Claim
18 words
An apparatus according to claim 3, wherein: said alternator is a three phase alternator having three stator windings.
Claim 10
Dependent Claim
25 words
An apparatus according to claim 3, wherein: said control circuit includes oscillator means for producing a carrier frequency upon which said pressure pulses are modulated.
Claim 11
Dependent Claim
20 words
An apparatus according to claim 9, wherein: said pressure pulses are modulated according to a frequency shift keying (FSK) scheme.
Claim 12
Dependent Claim
109 words
An apparatus according to claim 6, wherein: said control circuit comprises oscillator means for providing a constant reference frequency; selectable divider means coupled to said oscillator means for selectably dividing said constant reference frequency to produce a desired output frequency; frequency comparator means coupled to said divider means and to said tachometer means for comparing said rotational speed of said alternator with said desired output frequency; and pulse width modulator means coupled to said frequency comparator means and to said at least one stator winding of said alternator for selectively shorting said at least one stator winding so that said rotational speed is equal to said desired output frequency.
Claim 13
Dependent Claim
31 words
An apparatus according to claim 11, wherein: said selectable divider means is coupled to a sensor means for sensing conditions in said borehole and providing output data to said selectable divider.
Claim 14
Dependent Claim
14 words
An apparatus according to claim 12, wherein: said output data is binary coded data.
Claim 15
Dependent Claim
17 words
An apparatus according to claim 13, wherein: said desired output frequency is varied between two predetermined frequencies.
Claim 16
Dependent Claim
21 words
An apparatus according to claim 14, wherein: said rotational speed of said alternator is varied between substantially 7,100 and 8,000 RPM.
Claim 17
Dependent Claim
19 words
An apparatus according to claim 14, wherein: said two predetermined frequencies are located substantially between 15 and 20 Hz.
Claim 18
Dependent Claim
73 words
An apparatus according to claim 3, further comprising: h) electrical power storage means coupled to said at least one stator winding and to said control circuit, wherein said alternator charges said electrical power storage means and provides power for said control circuit when said at least one stator winding is not shorted, and said electrical power storage means provides power for said control circuit when said at least one stator winding is shorted.
Claim 19
Dependent Claim
15 words
An apparatus according to claim 17, wherein: said electrical power storage means is a capacitor.
Claim 20
Dependent Claim
81 words
An apparatus according to claim 12, further comprising: i) electrical power storage means coupled to said at least one stator winding and to said control circuit, wherein said alternator charges said electrical power storage means and provides power for said control circuit and said sensor means when said at least one stator winding is not shorted, and said electrical power storage means provides power for said control circuit and said sensor means when said at least one stator winding is shorted.
Claim 21
Dependent Claim
47 words
An apparatus according to claim 3, further comprising: h) a pressure compensator mounted adjacent said alternator, wherein said tool housing is filled with oil and said pressure compensator provides room for expansion and contraction of said oil in response to temperature and pressure changes in the borehole.
Claim 22
Independent Claim
145 words
An apparatus for use in a borehole having borehole fluid flowing therethrough, said apparatus comprising: a) a tool housing having an open upper end for receiving the borehole fluid; b) a drive shaft mounted for rotation in said housing; c) a turbine impeller mechanically coupled to said drive shaft and facing said open upper end such that the flowing borehole fluid causes said turbine impeller to rotate; d) a modulator rotor mechanically coupled to said drive shaft downstream from said turbine impeller such that rotation of said turbine impeller causes said modulator rotor to rotate; e) a modulator stator mounted in said housing adjacent said modulator rotor such that rotation of said modulator rotor relative to said modulator stator creates pressure pulses in the borehole fluid; and f) a controllable braking means for selectively braking rotation of said modulator rotor to modulate said pressure pulses.
Claim 23
Independent Claim
145 words
An apparatus for use in a borehole having borehole fluid flowing therethrough, said apparatus comprising: a) a tool housing having an open upper end for receiving the borehole fluid; b) a drive shaft mounted for rotation in said housing; c) a turbine impeller mechanically coupled to said drive shaft and facing said open upper end such that the flowing borehole fluid causes said turbine impeller to rotate; d) a modulator rotor mechanically coupled to said drive shaft downstream from said turbine impeller such that rotation of said turbine impeller causes said modulator rotor to rotate; e) a modulator stator mounted in said housing adjacent said modulator rotor such that rotation of said modulator rotor relative to said modulator stator creates pressure pulses in the borehole fluid; and f) a controllable braking means for selectively braking rotation of said modulator rotor to modulate said pressure pulses.
Claim 24
Dependent Claim
16 words
An apparatus according to claim 1, further comprising: g) an alternator coupled to said drive shaft.
Claim 25
Independent Claim
138 words
A method for modulating a pressure wave in a flow path of drilling fluid being circulated in a borehole, said method comprising: a) providing a turbine impeller in the flow path of the drilling fluid so that the circulation of the drilling fluid imparts rotation to said turbine impeller; b) mechanically coupling a modulator rotor to the impeller in the flow path so that rotation of said turbine impeller causes rotation of said modulator rotor; c) providing a modulator stator adjacent said modulator rotor so that rotation of said modulator rotor relative to said modulator stator interrupts the circulation of the drilling fluid and produces the pressure wave in the flow path of the drilling fluid; and d) selectively braking rotation of said modulator rotor to modulate the pressure wave in the flow path of the drilling fluid.
Claim 26
Independent Claim
138 words
A method for modulating a pressure wave in a flow path of drilling fluid being circulated in a borehole, said method comprising: a) providing a turbine impeller in the flow path of the drilling fluid so that the circulation of the drilling fluid imparts rotation to said turbine impeller; b) mechanically coupling a modulator rotor to the impeller in the flow path so that rotation of said turbine impeller causes rotation of said modulator rotor; c) providing a modulator stator adjacent said modulator rotor so that rotation of said modulator rotor relative to said modulator stator interrupts the circulation of the drilling fluid and produces the pressure wave in the flow path of the drilling fluid; and d) selectively braking rotation of said modulator rotor to modulate the pressure wave in the flow path of the drilling fluid.
Claim 27
Dependent Claim
24 words
A method according to claim 23, further comprising: e) coupling an alternator to said modulator rotor, said alternator having at least one stator winding.
Claim 28
Dependent Claim
37 words
A method according to claim 24, further comprising: f) monitoring the speed of rotation of said alternator; and g) selectively shorting said at least one stator winding to brake said alternator to a desired speed of rotation.
Claim 29
Dependent Claim
50 words
A method according to claim 24, further comprising: f) monitoring the speed of rotation of said alternator; g) selecting two desired speeds of rotation for said alternator; and h) selectively shorting said at least one stator winding to brake said alternator to one of said two desired speeds of rotation.
Claim 30
Dependent Claim
59 words
A method according to claim 26, wherein: said selective shorting of said at least one stator winding is in response to binary data; said alternator is braked to one of said two desired speeds in response to a binary 0; and said alternator is braked to the other of said two desired speeds in response to a binary 1.
Claim 31
Dependent Claim
18 words
A method according to claim 26, wherein: said two desired speeds differ by at least approximately 10 percent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-05-14 | 1999-11-13 | 2000-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-14 | 2003-11-13 | 2004-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-14 | 2007-11-13 | 2008-05-14 | $7700.00 | Window Closed / Lapsed |